Videoconferencing enables individuals located remotely one from the other to conduct a face-to-face meeting. Videoconferencing may be executed by using audio and video telecommunications. A videoconference may be between as few as two sites (point-to-point), or between several sites (multi-point). A conference site may include a single participant (user) or several participants (users). Videoconferencing may also be used to share documents, presentations, information, and the like.
Participants may take part in a videoconference via a videoconferencing endpoint (EP), for example. An endpoint (EP) may be a terminal on a network, for example. An endpoint may be capable of providing real-time, two-way, audio/visual/data communication with other terminals and/or with a multipoint control unit (MCU). An endpoint (EP) may provide information/data in different forms, including audio; audio and video; data, audio, and video; etc. The terms “terminal,” “site,” and “endpoint” may be used interchangeably. In the present disclosure, the term endpoint may be used as a representative term for above group.
An endpoint may comprise a display unit (screen), upon which video images from one or more remote sites may be displayed. Example endpoints include POLYCOM® VSX® and HDX® series endpoints, each available from Polycom, Inc. (POLYCOM, VSX, and HDX are registered trademarks of Polycom, Inc.) A videoconferencing endpoint may send audio, video, and/or data from a local site to one or more remote sites, and display video and/or data received from the remote site(s) on its screen (display unit).
Video images displayed on a screen at an endpoint may be displayed in an arranged layout. A layout may include one or more segments for displaying video images. A segment may be a predefined portion of a screen of a receiving endpoint that may be allocated to a video image received from one of the sites participating in the videoconferencing session. In a videoconference between two participants, a segment may cover the entire display area of the screens of the endpoints. In each site, the segment may display the video image received from the other site.
An example of a video display mode in a videoconference between a local site and multiple remote sites may be a switching mode. A switching mode may be such that video/data from only one of the remote sites is displayed on the local site's screen at a time. The displayed video may be switched to video received from another site depending on the dynamics of the conference.
In contrast to the switching mode, in a continuous presence (CP) conference, a conferee (participant) at a local endpoint may simultaneously observe several other conferees from different endpoints participating in the videoconference. Each site may be displayed in a different segment of the layout, which is displayed on the local screen. The segments may be the same size or of different sizes. The combinations of the sites displayed on a screen and their association to the segments of the layout may vary among the different sites that participate in the same session. Furthermore, in a continuous presence layout, a received video image from a site may be scaled, up or down, and/or cropped in order to fit its allocated segment size. It should be noted that the terms “conferee,” “user,” and “participant” may be used interchangeably. In the present disclosure, the term conferee may be used as a representative term for above group.
An MCU may be used to manage a videoconference. An MCU is a conference controlling entity that is typically located in a node of a network or in a terminal that receives several channels from endpoints and, according to certain criteria, processes audio and/or visual signals and distributes them to a set of connected channels.
Exemplary MCUs include the MGC-100 and RMX 2000®, available from Polycom Inc. (RMX 2000 is a registered trademark of Polycom, Inc.). Some MCUs may be composed of two logical units: a media controller (MC) and a media processor (MP). A more thorough definition of an endpoint and an MCU may be found in the International Telecommunication Union (“ITU”) standards, including the H.320, H.324, and H.323 standards. Additional information regarding the ITU standards may be found at the ITU website www.itu.int.
In a CP videoconferencing session, the association between sites and segments may be dynamically changed according to the activities taking part in the conference. In some layouts, one of the segments may be allocated to a current speaker, for example. The other segments of that layout may be allocated to other sites that were selected as presented sites or presented conferees. A current speaker may be selected according to certain criteria, including having the highest audio signal strength during a certain percentage of a monitoring period. The other presented sites, may include the image of the conferee that was the previous speaker; the sites having audio energy above a certain thresholds; certain conferees required by management decisions to be visible; etc.
In a conventional CP videoconference, each layout is associated with a video output port of an MCU. A conventional video output port may comprise a CP image builder and an encoder. A conventional CP image builder may obtain decoded video images of each one of the presented sites. The CP image builder may scale and/or crop the decoded video images to a required size of a segment in which the image will be presented. The CP image builder may further write the scaled image in a CP frame memory in a location that is associated with the location of the segment in the layout. When the CP frame memory is completed with all the presented images located in their associated segments, the CP image may be read from the CP frame memory by the encoder.
The encoder may encode the CP image. The encoded and/or compressed CP video image may be sent toward the endpoint of the relevant conferee. A frame memory module may employ two or more frame memories, for example, a currently encoded frame memory and a next frame memory. The memory module may alternately store and output video of consecutive frames. Conventional output ports of an MCU are well known in the art and are described in a plurality of patents and patent applications. A reader who wishes to learn more about a conventional output port is invited to read U.S. Pat. No. 6,300,973, for example, the content of which is incorporated herein by reference in its entirety.
A user's experience of videoconference is typically limited to one or more high-resolution two-dimensional displays. Although 3D (3-dimension) technologies have become more and more popular in other different fields, such as movies, media entertainment, etc., obstacles have prevented the 3D technology from being implemented by the videoconference industry. These obstacles include the need to wear special 3D glasses and the use of expensive cameras and displays. Creation of holograms may require special screens, cameras, and hardware that are very expensive, etc. Therefore, it is not realistic to expect conventional videoconferencing users to pay such high costs. Nor is it realistic to expect conventional videoconferencing users to sit in a videoconference wearing 3D glasses, which would be visible to other conferees.
Furthermore, many companies have invested in a conventional 2D video conferencing infrastructure. Those companies would like to keep their capital investment in their current video conferencing infrastructure that does not support current existing 3D video conferencing techniques.
The above-described deficiencies in videoconferencing do not limit the scope of the inventive concepts of the present disclosure in any manner. The deficiencies are presented for illustration only.